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The effect of ovarian and hypophyseal hormones on mammary gland epithelial cell proliferation.

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The Effect of Ovarian and Hypophyseal Hormones on
Mammary Gland Epithelial Cell Proliferation '
HAROLD H. TRAURIG AND CHARLES F. MORGAN
Department of Anatomy, University of Minnesota Medical School,
Minneapolis, Minnesota
ABSTRACT
Castrated and castrated and hypophysectomized female mice (BALB/c)
were injected subcutaneously with estradiol-17p (0.5 fig or 1.0 pg/day) and progesterone
(1.0 mg or 3 mg/day) in addition to prolactin (1.0 mg), oxytocin (1.0 IU) or
growth hormone (1.0 mg), alone and in combination for 10 or 15 days. Twenty-four
hours after the last hormonal treatment, tritiated thymidine (0.7 ,uc/gram body weight)
was injected intravenously, and the mice sacrificed six hours later. Tissue from the
inguinal mammary glands was removed and processed for radioautographic, histological and whole mount study.
Radioautographs of hematoxylin stained sections of mammary tissue from each
animal were selected. Under oil immersion, 2,000 epithelial cells were consecutively
counted and the number of labeled cells noted. Results are expressed as the per cent of
labeled epithelial cells.
All hormonal treatment, except oxytocin alone, caused a significant increase in
per cent of labeled cells as compared to castrated, untreated animals. The per cent
of labeled cells depended, in general, on the dosage and duration of treatment. Combinations of growth hormone with estradiol-17p and progesterone did not augment epithelial proliferation. The addition of oxytocin or prolactin to the estradiol-17p (0.5 fig)
- progesterone (1.0 mg) combination significantly increased the per cent of labeled
cells.
Prolactin, but not oxytocin, augmented epithelial proliferation in similarly treated
castrated and hypophysectomized mice. Combinations of estradiol-17P ( 1.0 pg) and
progesterone (3.0 mg) with oxytocin or prolactin did not significantly augment epithelial proliferation as compared to ovarian steroid treatment alone.
The mammary gland may react to hormonal treatment in several ways. Increased cellular proliferation, hypertrophy
and differentiation of existing epithelial
elements and the initiation of secretory activity may result. In order to understand
the mechanism of action of hormonally active substances on the mammary gland it
is important to measure the contribution
of each of these responses to hormonal
stimulation.
Many quantitative methods have been
employed to measure the reaction of the
mammary gland to hormonal treatment.
Investigators have reported subjective descriptions of mammary gland whole mount
preparations (Turner and Gomez, ' 3 3 ) and
others have used arbitrary rating schemes
to measure mammary growth and secretion (Nandi and Bern, '60). The measurement of the per cent of mammary parenchyma from projected histological slides
was a more precise quantitative technique
used by Benson and Folly ('57) and Meites
and Nicoll ('59). Kirkham and Turner
ANAT.REC., 150: 423-434.
('53) have used biochemical determinations of total mammary gland DNA as an
index of mammary gland growth.
The development of high resolution
radioautography, using tritiated thymidine
a specific precursor for DNA, has made it
possible to accurately quantitate cell proliferation. This technique has been applied by Traurig and Morgan ('64) to the
investigation of mammary epithelial cell
proliferation in mice treated with ovarian
steroids.
The current investigation utilized radioautography to study the effect of certain
hypophyseal hormones, alone and in combination with ovarian steroids, on the proliferation of the mammary gland epithelium in the mouse. Epithelial proliferation
was compared to the degree of mammary
1 This
investigation was supported by grants
GM07762,and 26114 from U: S..Public Health Service.
A preliminary report of this znvestlgation was .presented at the 77th Pmnual Meetmg of the American
Assoociation of Anatomists. (Anat. Rec., 148: 345,
'64. )
2 Present address: Department of Anatomy, University of Kentucky Medical School, Lexmgton, Kentucky.
3Deceased, March 10, 1964.
423
424
HAROLD H. TRAURIG AND CHARLES F. MORGAN
lobule-alveolar differentiation observed in
whole mount and histological preparations
in treated and untreated mice.
MATERIALS AND METHODS
Eighty-two nine-week-old female BALB/c
mice were oophorectomized using a dorsal
approach. After a ten-day recovery period,
the success of oophorectomy was verified
by the absence of cornified cells in vaginal
smears for several days before hormonal
treatment was begun. Nine oophorectomized mice were hypophysectomized via
the parahyaryngeal approach and allowed
to recover for five days before hormonal
treatment. Completeness of hypophysectomy was verified post mortem by a study
of serial sections of the sella turcica, hypothalamus and surrounding tissue. The animals were grouped and treated with combinations of estradiol - 17 B (0.5 vg or
1.0 clg/day), progesterone (1.0 mg or 3.0
mg/day), oxytocin (1.O IU/day), prolactin
( 1 5 IU/mg; 1.0 mg/day) and growth hormone (equipotent with USP reference
standard; 1.0 m g / d a ~ ) as
~ outlined in
tables 1, 2 and 3 . Three oophorectomized
mice given daily injections of vegetable oil
(sesame oil) and four oophorectomized
mice given no injections served as untreated controls.
Ovarian steroids and hypophyseal hormones were dissolved and diluted in vegetable oil and saline respectively, to yield a
final injection volume of 0.05 cm3. All injections were given subcutaneously in the
dorsal thoracic region at midday for 10
or 15 days.
Twenty-four hours after the last hormonal treatment, tritiated thymidine (0.7
clc/gram body weight; specific activity
5.2c/mM) was injected intravenously and
the mice sacrificed six hours later.
To reduce possible error due to tissue
sampling, only the inguinal pairs of mammary glands were used for study. The
glands from one side of the animal were
used to prepare hematoxylin stained whole
mounts. From the remaining pair of
glands, tissue surrounding the large lymph
node under the nipple was removed for
further histological and radioautographic
processing. All tissue samples were fixed in
Bouin’s fluid over night. The tissue blocks
for radioautography were embedded in
paraffin and sectioned parallel to the abdominal surface of the mammary gland.
Tissue sections used for radioautographic
analysis were of those passing approximately through the center of the lymph
node embedded in the mammary gland.
Adjacent sections, cut at 5 p, were stained
with hematoxylin and eosin for histological study. Tissue sections for radioautography were cut at 2 LI and processed
according to the dipping and stripping
techniques described by Kopriwa and Leblond (’62) and Pelc (’56). After 17 days
exposure, the radioautographs were developed in D-19 or D-17 Kodak developer,
fixed in Kodafix and stained with hematoxylin. Radioautographic preparations
with negligible background were selected
and scanned under oil immersion until a
mammary epithelial structure (any duct,
end bud or alveolus) appeared in the field.
The number of cells composing the epithelial structure was counted and the number
demonstrating an incorporation of tritiated
thymidine into their nuclei was determined. A cell was considered to have incorporated tritiated thymidine if more
than three reduced silver grains could be
visualized in the emulsion above its nucleus. Scanning of the sections was continued, including all epithelial structures
as they were encountered, until a minimum of 2,000 epithelial cells had been
counted for each animal. The labeling index, or per cent of epithelial cells labeled
with tritiated thymidine, was determined
and the mean calculated for each group.
The standard error of the mean was calculated and all data were tested for significance ( P < 0.05) by use of Student’s “t”
test.
The validity for using tritiated thymidine to label proliferating cells is discussed
by Leblond, Messier and Kopriwa (’59)
and Traurig and Morgan (’64).
RESULTS
The animals in Group 1 (table 1) received no hormonal treatment, however,
three of the seven animals were injected
with the vegetable oil vehicle for ten days.
4 The authors wish to thank the following for gifts
of hormones. Estradiol-17@ and progesterone from
Dr. Edward Henderson Schering Co. Prolactin and
growth hormone from ’Endocrinology Study Section
NIH. Oxvtocin (Pitocin) from Dr. F. C. Armstrone;
-.
Parke, Davis and Co.
‘
425
MAMMARY EPITHELIAL PROLIFERATION
TABLE 1
The e f f e c t of one hypophyseal hormone alone on the labeling index of mammary gland
epithelial cells I in oophorectumized mice
Group
no.
Hormonal treatment
Treatment period - 10 days
Animals
Labeling
index
Standard
error of
mean
in group
1
None
7
0.1
f0.06
2
0 (1.0 IU/day)
7
0.1
f0.04
3
LTH (1.0 mg/day)
4
2.7
f0.75
4
STH (1.0 mg/day)
4
1.2
-+ 0.39
STH, growth hormone; LTH, prolactin; 0, oxytocin.
Per cent of tritiated thymidine labeled cells in 2,000 epithelial cells.
(Traurig and Morgan, '64), presented here for comparison.
* Published previously
Since no difference was noted between the
oil injected and uninjected animals, the
data was pooled. Tritiated thymidine labeled epithelial cells were observed in
radioautographic preparations of four of
the seven mice and the highest individual
labeling index (per cent of labeled cells of
2,000 mammary epitheIia1 cells) was
0.4%. The mean labeling index of the
group was 0.1%. Study of whole mount
preparations revealed ductal systems consisting of thin, lightly stained lobar ducts
with little branching or end bud formation
(fig. 1). Histologically, the ductal epithelium was composed of low cuboidal cells.
Hypophyseal hormones alone (see table 1
for details of hormonal treatment)
Oxytocin ( 0 ) (1.0 IU/day) alone had
no detectable effect on the mammary gland
epithelium. Whole mounts and histological preparations resembled those of the untreated group (fig. 2 ) . The mean labeling
index of the oxytocin treated group was
0.1%. No labeled cells were observed in
two of the seven mice and the highest individual value was 0.4%.
The group receiving prolactin (LTH)
alone ( 1 mg/day) yielded a mean labeling
index of 2.7% which was significantly
greater than the untreated group (P <
0.01). Although examination of whole
mount preparations showed various sized
ducts, there was no indication of alveolar
formation (fig. 4).
The administration of growth hormone
(STH) (1 mg/day) also promoted a significantly greater mean labeling index
(1.2% ) as compared to the untreated
group ( P < 0.01). No alveolar differentia-
tion was noted in whole mount preparations (fig. 3 ) .
Combination of hypophyseal hormones
with estrogen and progesterone.
Two dosages of estradiol-l7D ( E ) and
progesterone ( P ) were used. They are
referred to as the high or low dosage of
ovarian steroids in this report (see tables
2 and 3 for details).
Hypophyseal hormones combined with the
high dosages of ovarian steroids
(table 2)
The administration of the high dosage
of ovarian steroids alone (E, 1.0 wg/day
plus P, 3.0 mg/day) for 15 days resulted
in a labeling index of 8.9%. Labeled cells
were observed in the epithelium of developing alveolar structures and ducts of all
sizes. Studies of whole mount and histological preparations revealed developing
lobular ducts and some alveolar differentiation (fig. 6).
The combination of LTH ( 1 mg), 0
( 1 I U ) or LTH plus 0 with the high dosage of ovarian steroids did not promote a
significant increase in the labeling index
as compared to the E f P treatment (table
2). However, the addition of the hypophyseal hormones did augment the degree
of lobule-alveolar differentiation, especially in the group receiving E P LTH
0 where histological evidence of secretion was noted (fig. 12).
+
+ +
Hypophyseal hormones combined with the
low dosage of ovarian steroids (table 3)
Treatment with the low dosage of ovarian steroids alone (E, 0.5 ug/day plus P,
426
HAROLD H. TRAURIG AND CHARLES F. MORGAN
TABLE 2
The e f f e c t of high dosages of estradiol - 178 and progesterone combined w i t h hypophyseal
hormones on the labeling index of mammary gland epithelial cells
in oophorectomized mice
Animals
in group
Labeling
index
Standard
error of
mean
3
8.9
a0.81
E + P + O (l.OIU/day)
3
9.5
f 1.10
7
E+P+LTH (1.0 mg/day)
3
11.0
f 1.92
8
E+P+LTH+03
3
9.7
.+. 0.69
Group
no.
Hormonal treatment
Treatment period - 15 days
5
E ( 1 pg/day) + P ( 3 mg/day)
6
%a3
E, estradiol - 17p; P, progesterone; 0,oxytocin; LTH, prolactin.
1 Per cent of trifiated thymidjne labeled cells in 2,000 epithelial cells.
2 Publlshed previously (Traung and Morgan, '64 , presented here for comparison.
3 E was given alone days 1-5, then E + P + hypopkyseal hormones on days 6-15.
TABLE 3
The e f f e c t of low dosages of estradiol - 1 7 p and progesterone combined w i t h hypophyseal
hormones on the labeling index of mammary gland epithelial cells * in
oophorectomized and oophorectomized-hypophysectomized mice
~
~~
Group
no.
Hormonal treatment
Treatment period
10 days
9
E (0.5 pg/day) + P (1.0 mg/day)
-
10
E + P + S T H (l.Omg/day)
11
E + P + O (l.OIU/day)
12
E + P + O ~*
2~
3
3
Standard
error of
mean
Animals
in group
Labeling
index
6
2.4
f
5
2.8
& 0.25
9
5.9
f0.88
5
1.3
-t 0.16
0.23
13
E + P + L T H (l.Omg/day)
4
6.7
2 0.54
14
E+P+LTH
5
8.0
f0.92
15
E+P+LTH+O
6
12.4
f 1.14
16
E+P+LTH+STH
3
10.5
k3.04
17
E+P+LTH+STH+03
5
10.2
f 1.26
3 *
E, estradiol - 176; P, progesterone; 0,oxytocin; LTH, prolactin; STH, growth hormone.
1 Per cent of tritiated thymidine labeled cells in 2,000 epithelial cells.
2 Published previously (Traurig and Morgan, '64), presented here for comparison.
3E was given alone days 1-5, then P+hypophyseal hormones on days 6-10.
* Oophorectomized-hypophysectomized mice.
1 mg/day) for ten days resulted in a labeling index of 2.4%. Whole mount preparations showed a ductal system consisting
of some lobular ducts and small end buds,
but no evidence of alveolar formation
(fig. 5 ) .
The addition of STH to the low dosage
of E P did not significantly augment the
labeling index observed with the low dosage of E P alone, Whole mount preparations differed only in that the E P
STH group showed some dilated ducts and
large end buds. The labeling index of
+
+
+ +
+ +
6.7% with the E P LTH combination
was significantly greater ( P < .001) than
that of E P alone. In addition, definite
initiation of lobule-alveolar differentiation
was observed in whole mount and histological preparations (fig. 11). E P 0
also significantly (P < .01) augmented the
labeling index as compared to that of the
E P treatment. The mean of the group
was 5.9% and the individual labeling indices ranged from 3.3% to 10.4% all of
which were numerically greater than the
mean labeling index of the E P group.
+
+ +
+
+
MAMMARY EPITHELIAL PROLIFERATION
However, differences in degree of lobulealveolar development between these groups
were not observed consistently in whole
mount and histological preparations (fig.
9).
Combinations of E P+ LTH 0, E
P LTH STH and E P LTH f STH
0 yielded labeling indices of 12.4%,
10.5% and 10.2% respectively (table 3 ) .
Whole mount studies (fig. 7) revealed
considerable lobule-alveolar differentiation
and histological examination showed some
evidence of secretary activity. Tritiated
thymidine labeled epithelial cells were
noted in ducts of all sizes as well as in the
developing alveolar structures.
The oophorectomized-hypophysectomized
mice receiving E P 0 (table 3) showed
a mean labeling index of 1.3%. This was
significantly ( P < .Ol) less than the 5.9%
value observed in similarly treated oophorectomized animals, but significantly
( P < .OOl) greater than that of untreated,
oophorectomized mice. Observations of
whole mount preparations showed the
ductal systems of the oophorectomizedhypophysectomized group receiving E P
0 to be somewhat less extensive than
the oophorectomized animals receiving
E P, but more extensive than the untreated, oophorectomized group (figs. 1,
5 and 8 ) .
The E
P
LTH treatment in oophorectomized-hypophysectomized mice resulted in a mean labeling index of 6 . 7 % .
This was significantly greater than that of
the E P treatment in oophorectomized
mice ( P < .001) and E P 0 treatment
in oophorectomized - hypophysectomized
animals ( P < .OOl). However, it was not
significantly different from that of similarly treated oophorectomized mice. Whole
mount preparations of the oophorectomized-hypophysectomized group treated
with E P LTH showed considerable
duct branching but no alveolar differentiation as observed in similarly treated oophorectomized mice. End buds on lobar and
lobular ducts were, in many instances,
notably enlarged and darkly stained (figs.
10 and 11 ). Histological observations revealed ductal epithelium three to five cell
layers thick and radioautographic preparations showed the epithelium of end bud
structures to contain many labeled cells.
+
+
+
+
+ +
+
+
+ +
+
+
+
+ +
+
+ +
+ +
427
DISCUSSION
This investigation has demonstrated the
usefulness of radioautography to study the
effects of ovarian and hypophyseal hormone treatment on mammary gland
growth. The results of numerous studies
of mammary growth and function have
shown that a certain hormonal treatment
may manifest its effect on the mammary
gland in several ways. Epithelial cell proliferation may be enhanced, the development and extension of lobar and lobular
ducts and the differentiation of alveoli
may result or secretory activity may be
initiated .
Kirkham and Turner ('53) have used
total organ DNA content to quantitate the
influence of pregnancy, lactation and experimental hormonal treatment on mammary gland cell proliferation. This technique measured the DNA from all cell
types without discrimination. The contribution of DNA from connective, vascular and nervous tissue cells can influence
the results, especially during the early
phases of mammary growth and development when the epithelial component is
relatively small. In contrast, radioautography permitted a quantitation of only the
mammary epithelial cells. In addition,
Leblond, Messier and Kopriwa ('59) have
used tritiated thymidine and radioautography to measure cell proliferation in
many tissues while, in an earlier report,
Traurig and Morgan ('64) extended the
use of this technique to a study of the
influence of ovarian hormones alone on
mammary epithelial proliferation.
This study demonstrated that prolactin
alone caused mammary epithelial proliferation (figs. 1 and 4 ) . Lyons ('42) and
Mizune, Iida and Naito ('55) and Mizuno
and Naito ('56), using whole mount and
DNA measurement techniques, reported
similar results by showing that intraductal
prolactin administration promoted mammary gland growth. Using radioautography, this investigation has shown that
prolactin combined with ovarian steroids
augmented mammary epithelial proliferation as well as lobule-alveolar differentiation compared to ovarian steroids alone
(tables 2 and 3; figs. 5 and 11).
Nandi ('58) has reported that growth
hormone was as effective as prolactin in
428
HAROLD H. TRAURIG A N D CHARLES F. MORGAN
stimulating mammary growth and differentiation in mice in which the mammary
cancer incidence is high. Later, Nandi
and Bern ('60) suggested that growth hormone was less effective in promoting mammary growth and development in strains
of mice with a low incidence of mammary
cancer such as the BALB/c mice used in
the present investigation.
Since E P STH treatment did not
significantly augment epithelial proliferation above the E P treatment, the present study supports the results reported by
Nandi and Bern ('60). It has been demonstrated, however, that growth hormone
alone promoted some mammary epithelial
proliferation in oophorectomized mice
compared to untreated mice (table 1; figs.
1 and 3 ) . In addition, a definite increase
in the degree of lobule-alveolar differentiation was noted in whole mount preparations from animals receiving growth hormone plus ovarian steroids and prolactin
(fig. 7).
Recently, Benson and Folley ('57) reported that exogenous oxytocin was able
to prevent the involution of post-lactation
mammary parenchyma in castrated but
not in hypophysectomized rats. They theorized that oxytocin caused the release of
hypophyseal prolactin which, in turn, prevented mammary involution. Although
Meites and Hopkins ('61) confirmed the
observation of Benson and Folley, they
contended that oxytocin prevented mammary involution by stimulating the contraction of alveoli and the evacuation of
alveolar secretion rather than through the
release of hypophyseal prolactin. Meites
and Hopkins strongest basis of objection
was a report by Meites, Talwalker and
Nicoll ('60) describing the failure of oxytocin to initiate lactation in rats and rabbits. However, Haun ('59) had previously
reported that oxytocin was able to initiate
mammary lactation in rabbits. Also Grosvenor and Turner ('58) were unable to
demonstrate a discharge of hypophyseal
prolactin in the rat following oxytocin
administration.
In the current investigation, oophorectomized and oophorectomized-hypophysectomized, virgin mice were used to determine whether oxytocin could influence
hypophyseal function. It has been shown
+ +
+
in this study in female mice (table 1 )
and others in female rabbits (Lyons, '42;
Mizuno et al., '55, '56) that prolactin alone
promotes mammary growth while Bradby
and Clarke ('56) showed that oxytocin
alone has no effect on the mammary
gland. Therefore, if oxytocin can cause
the release of hypophyseal prolactin, it
should augment mammary epithelial proliferation. According to a recent report by
Walthuis ('63) the hypophysis of oophorectomized mice contained little prolactin.
Thus, the administration of oxytocin alone
to oophorectomized mice could not be very
effective. This is confirmed by the data
presented here (table 1; figs. 1 and 2).
On the other hand, Hymer, McShan and
Christiansen ('61) have shown that estrogen treatment greatly increased the hypophyseal prolactin content. Therefore, if
oxytocin can release hypophyseal prolactin
it should augment mammary epithelial
cell proliferation in oophorectomized mice
treated with E P 0 as compared to
E P treatment. The data in table 3
show that, compared to E P treatment,
E P +LTH augmented mammary epithelial cell proliferation in oophorectomized and oophorectomized-hypophysectomized mice while E P 0 augmented
cell proliferation only in oophorectomized
mice.
This study does not conclusively prove
that oxytocin caused the release of prolactin from the hypophysis although this
is the most attractive explanation at this
time. Alternate explanations may be offered. Oxytocin extracts may contain
some as yet unidentified "releasing factor"
that can influence hypophseal function, or
the release of hypophyseal mammogenic
factors may be a result of the dosage of
exogenous oxytocin (1.0 IU/day) used in
these experiments. It has been reported
by Benson, Cowie, Folley and Tindall
('59) that as little as 250 mu of oxytocin
will permit a litter to obtain milk from an
anesthetized, lactating rat. Later, Benson,
Folley and Tindall ('60) reported that two
synthetic oxytocin preparations successfully retarded post lactation mammary involution in the rat. This evidence strongly
suggested that oxytocin can influence the
secretion of hypophyseal hormones.
+
+
+ +
+
+ +
MAMMARY EPITHELIAL PROLIFERATION
Other investigations have suggested that
oxytocin promoted the release of hypophyseal prolactin or ACTH. After injection of oxytocin, Benson and Folley ('57)
observed vaginal mucification in the rat.
Martini and de Poli ('56) and Rinne,
Kivalo, and Lahtinin ('59) reported a depletion of adrenal ascorbic acid and Martini and de Poli ('56) a decrease in circulating eosinophils following exogenous
oxytocin.
This study has demonstrated the importance of assessing epithelial cell proliferation as well as ductal and alveolar
differentiation in studies concerning the
hormonal regulation of mammary development. Of special interest is the difference in alveolar differentiation seen in
E P f LTH treated oophorectomized
mice as compared to similarly treated
oophorectomized and hypophysectomized
mice. In spite of the observation (table 3)
that the labeling indices of these two
groups were not significantly different, the
oophorectomized and hypophysectomized
group apparently lacked other hormonal
factors needed for normal mammary differentiation (figs. 10 and 11).
+
CONCLUSIONS
( 1 ) In oophorectomized mice, prolactin
,stimulated mammary epithelial proliferation as well as lobule-alveolar differentiation.
( 2 ) Under experimental conditions oxyibocin may influence the secretion of hypophyseal hormones.
( 3 ) Under the conditions of this investigation, growth hormone had little influence on the proliferation of mammary
epithelium, but markedly augmented
lobule-alveolar differentiation in hormonal
combinations including estrogen, progesterone and prolactin.
( 4 ) Other hormones, in addition to estrogen, progesterone and prolactin, are
required for full ductal and alveolar development in the mammary glands of the
oophorectomized and hypophysectomized
rnouse.
LITERATURE CITED
Benson, G. K. 1960 Pituitary-Adrenal relationships in the retardation of mammary gland
involution by oxytocin. J. Endocr., 20: 91-100.
429
Benson, G. K.,and S. J. Folley 1957 The effect
of oxytocin on mammary gland involution in
the rat. J. Endocr., 16: 189-201.
Benson, G. K., S. J. Folley and J. S. Tindall
1960 Effects of synthetic oxytocin and valyl
oxytocin on mammary involution in the rat.
J. Endocr., 20: 106-111.
Benson, G. K., A. T. Cowie, S. J. Folley and J. S.
Tindall 1959 Recent Progress in the Endocrinology of Reproduction. Ed. by C. w. Lloyd.
Academic Press, New York. pp 457498.
Bradley, T. R., and P. M. Clarke 1956 Response of rabbit mammary gland to locally
administered prolactin. J. Endocr., 14: 28-36.
Grosvenor, C. E., and C. W. Turner 1958 Effects of oxytocin and blocking agents upon
pituitary lactogen discharge in lactating rats.
Proc. SOC. Exp. Biol. (N. Y,),97: 463467.
Haun, C. K. 1959 Induction of lactation in the
rabbit with oxytocin. Anat. Rec., 133: 286.
Hymer, W. C., W. H. McShan and R. G. Christiansen 1961 Electron microscopic studies
of anterior pituitary glands from lactating and
estrogen treated rats. Endocrinology, 69:
81-90.
Kirkham, W. R., and C. W. Turner 1953 Nucleic acids of the mammary glands of rats.
Proc. SOC.Exper. Biol. (N. Y . ) , 83: 123-126.
Kopriwa, B. M.,and C. P. Leblond 1962 Improvements in the coating technique of autoradiography. J. Histochem. Cytochem., 10:
269-284.
Leblond, C. P., B. Messier and B. Kopriwa 1959
Tritiated thymidine as a tool for the investigation of the renewal of cell populations. Lab.
Invest., 8: 296-308.
Lyons, W. R. 1942 The direct mammotrophic
action of lactogenic hormone. Proc. SOC.Exp.
Biol. ( N . Y . ) , 51: 308-311.
Martini, L., and A. de Poli 1956 Neurohormonal control of the release of ACTH. J. Endocr., 13: 229-234.
Meites, J., and T. F. Hopkins 1961 Mechanism
of action of oxytocin in retarding mammary
involution: Study in hypophysectomized rats.
J. Endocr., 22: 207-213.
Meites, J., and C. S. Nicoll 1959 Hormonal
prolongation of lactation for 75 days after
litter withdrawal in postpartum rats. Endocr.,
65: 572-579.
Meites, J., P. K. Talwalker and C. S. Nicoll 1960
Failure of oxytocin to initiate mammary secretion in rabbits or rats. Proc. SOC.Exp. Biol.
(N. Y.), 105: 467469.
Mizuno, H., and M. Naito 1956 The effect of
locally administered prolactin on the nucleic
acid content of the mammary gland of the
rabbit. Endocr. Jap., 3: 227-230.
Mizuno, H., K. Iida and M. Naito 1955 The
role of prolactin in the mammary alveolus
formation. Endocr. Jap., 2: 163-169.
Nandi, S. 1958 Role of somatotropin i n mammogenesis and lactogenesis in C,H/HeCRGL
mice. Science, 128: 772-774.
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HAROLD H. TRAURIG AND CHARLES F. MORGAN
Nandi, S., and H. A. Bern 1960 Relation between mammary gland responses to lactogenic
hormone combinations and tumor susceptibility in various strains of mice. J. Nat. Cancer
Inst., 24: 907-931.
Pelc, S. R. 1956 The stripping-film technique
of autoradiography. Int. J. Appl. Radiation
and Isotopes, 1 : 172-177.
Rinne, U. K., E. Kivalo and K. Lahtinin 1959
Studies for the corticotrophin releasing activity
of synthetic oxytocin. Acta Endo., 32: 589-595.
Traurig, H. H. 1963 Autoradiographic study of
the growth of the mammary gland under hormonal influence in castrated and castrated-
hypophysectomized mice. Ph.D. Thesis. University of Minnesota.
Traurig, H. H., and C. F. Morgan 1964 Autoradiographic studies of the epithelium of the
mammary gland as influenced by ovarian hormones. Proc. SOC.Exp. Biol. (N. Y.), 115:
1076-1080.
Turner, C. W.,and E. T. Gomez 1933 The
normal development of the mammary glands
of the male and female albino mouse. Res.
Bull. Missouri Agric. Exper. Sta., No. 182.
Walthuis, 0. L. 1963 The effect of sex steroids
on the prolactin content of hypophysis and
serum in rats. Acta Endo., 43: 137-146.
Abbreviations
0, Oxytocin
STH, Growth Hormone
E, Estradiol-17p
P, Progesterone
LTH, Prolactin
PLATE 1
EXPLANATION OF FIGURES
Mammary gland whole mount preparations demonstrating duct growth
and alveolar differentiation resulting from hormonal treatment.
Oophorectomized mouse. No hormonal treatment. 35 X.
Oophorectomized mouse. 1 IU O/day for ten days. 35 X.
Oophorectomized mouse. 1 mg STH/day for ten days. 35 X.
Oophorectomized mouse. 1 mg LTH/day for ten days. 35 X.
Oophorectomized mouse. 0.5 pg E/day plus 1 mg P/day for ten
days. 35 X.
Oophorectomized mouse. 1 pg E/day plus 3 mg P/day for 15 days.
35 x.
MAMMARY EPITHELIAL PROLIFERATION
Harold H. Traurig and Charles F. Morgan
PLATE 1
431
PLATE 2
EXPLANATION OF FIGURES
432
7
Oophorectomized mouse. 0.5 pg E, 1 mg P, 1 mg LTH plus 1 mg
STH/day for ten days. 35 x.
8
Oophorectomized and hypophysectomized mouse. 0.5 pg E, 1 mg P
plus 1 I U O/day for ten days. Some lobular duct branching, no
alveolar formation. 35 X .
9
Oophorectomized mouse. 0.5 pg E, 1 mg P, plus 1 IU O/day for ten
days. Lobular duct branching and some beginning alveolar formation. 35 X .
10
Oophorectomized and hypophysectomized mouse. 0.5 pg E, 1 mg P
plus 1 mg LTH/day for ten days. Formation of large end buds, no
alveolar differentiation. 35 X.
11
Oophorectoniized mouse. 0.5 pg E, 1 mg P plus 1 mg LTH/day for
ten days. Alveolar differentiation present. 35 x.
12
Oophorectomized mouse. 1 pg E, 3 mg P, 1 IU 0 plus 1 mg LTH/day
for 15 days. Extensive alveolar differentiation. 35 X.
MAMMARY EPITHELIAL PROLIFERATION
Harold H. Traurig and Charles F. Morgan
PLATE 2
433
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effect, epithelium, mammary, ovarian, gland, proliferation, hypophyseal, hormone, cells
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